Circuit breaker



Jan. I7, I928. 1,656,851

c. E. ANDERSON, ET AL 0 IRCUIT BREAKER Filed June 24, 1925 2 Sheets-Sheet l INVENTORQ CHRZ ERIC fl/vnzRso/v W: LL Inna H. KEEFE, Tia

ATTORNE 6 Q. vllllllllllill 1 I 4. I l 4 Jan. 17, 1928.

1,656,851 C. E. ANDERSON ET AL 0 IRCUIT BREAKER Filed June 24. 1925 2 Sheets-$heet 2 INVENTORS c,E. q/vosesonl.

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j H. KEEP 5,171

79 7 0mm l ATTORNEYS Patented Jan. 17,1928.

3 .UNITED STATES PATENT OFFICE.

cm ERIC mnnnson, or sTnATronn, snn wrLLmm 11. mars, 3a., or BRIDGEPOBT, ComCrIcnT, nssronons To Tan BRYANT ELECTRIC COMPANY, or BRIDGEPORT, GONNEGTICU'JJ, A CORPORATION or CONNECTICUT.

cmCoIT enema Application and June 24, 1925; Serial No. 39,312.

Our invention relates to circuit breakers, and particularly to a thermostatically con trolled circuit breaker. The mechanism is of a type such that it is notonly manually 6 operable to on and E positions, but also is automatically operated to open the circuit on overload. The special object of our invention is to provide means by which the automatic overload operation of the'mechanism is visibly indicated. For this purpose we employ in the specific embodiment of our invention illustrated, the manually operated thumb piece, or the like, which occupies certain indicating positions when the 1 mechanism is thrown to on or ofi position manually, and a different position when the circuit is automatically opened by overload.

It will of course be recognized that the underlying conception may 'be embodied in 20 other forms of indicators and is not confined to the specific mechanism which we use to illustrate the invention.

In the accompanying drawings- Fi 1 is a perspective of a circuit breaker 25 in which our invention is embodied in one form;

Fig. 2 is a plan view thereof with the cover removed and showing the mechanism in circuit closing position;

Figs. 3 and 4 are sections on the lines 33, 44, respectively, Fig. 2; and

Fig. 5 is a broken plan view showing the mechanism in'open circuit position following automatic operation on overload.

85 The mechanism here shown is mounted on an insulating base provided with a metal cover 16 having an insulating lining 17 Between the ofi'set end of the cover and the base 15 a slot 18 is afforded to permit the 40 play of an operating lever 19. At appropriate pointsadjacent theslot 18 are indi-' cator legends 20, 21 and 22, of which the legends and 22 register with the lever 19 in its respective on and oil positions 45 when operated manually by means of the insulating button 23. The intermediate legend 21 registers with the lever when the mechanism autoinatically assumes open cir cuit position incident to the deflection of the 60 thermostatic element hereinafter referred to. Circuit terminals 24 and 25 are mounted upon the base 15 and maybe of any appropriate character for establishing connection with wires, bus bars or shunts, as may be preferred. The terminal.24 is electrically connected through the thermostat and shunt as hereafter more specifically stated, with the stationary switch contact 26 through its at-- taching screw 27 The circuit terminal 25 is directly connected by a shunt strap and screw 28 with the base of the stationary contact 29. The spring brush endsof the contacts 26 and 29 lie in register adapted to be bridged by the circuit closer block 30.

The circuit closing block 30 is carried at the free end of a rock lever 31, pivoted in the notch 32 of the V-frame 33. The latter may be conveniently formed from a centrally apertured sheet metal stamping, the opposite sides of which are offset to form the parallel legs of the -V-frame, This frame is in turn pivoted at 34 to the upper and lower parallel branches'of a bracket 35 fixed in any appropriate fashion to the base. Lugs 36, outwardly ofiset from opposite sides of the bracket 35, form a pivotal support on which rocks the inner forked end of the operating,

lever 19. The latter is ofi'set at 37 to clear the V-shaped frame 33 while the bridge 38 between the legs of the lever aifords an anchor for one end of the operating spring 39, The other end of the spring, passing between the legs of the frame 33, is anchored at 40 to the rock lever 31.

In the normal position of the parts (Fig. 2), the pivoted frame 33 is supported by its lug 41 upon the shoulder 42 of a magnifying lever 43, pivoted on the stud 44 carried by the bracket 35. At its opposite or free end the lever 43 is shaped to form a latching nose 45 adapted to be engaged, by a catch 46 mounted through approximate insulation 47 aifthe free end of the thermostatic element 48. When the engagement between the catch 46 and the nose 45 is broken by movement of thermostatic element, the pressure exerted against the shoulder 42 of the lever-.43 by the lug 41 of the rocking frame 33 under the stress of spring 39, cause; the. ma ing lever 43 to swin away rom the i r e (Fig. 5),'thus permitting the lug .41 to escape the shoulder 42. The'cscape.

. pin is so predetermined that the pivot point 32 of the circuit breaker lever 31 is shifted across the plane of effort of the spring 39.

- Consequently the lever 31 is caused to swing to open circuit position as indicated in Fig. 5, while the operating lever 19 is caused to move away from its circuit closing position toward its manually operated off position. Before reaching the latter, however, it is halted by its impingement against the leg of the rocking frame 33, and therefore assumes an intermediate position in register with the intermediate ofi legend 21 on. the cover, and indicates the automatic operation of the circuit breaker by overload conditions on the line. This position of the parts is maintained, since the spring 39 is still under stress. 3

To restore the rocking frame 33 to normal position, the hand lever.19 must be swung to the ofi position assumed on manual opening of the circuit. As it moves in the direction of the arrow K, Fig. 5, its bearing against the leg 50 of the frame 33 swings the latter in the direction of the arrow Y (Fig. 5). The lug 41 of the frame now engages with the nose 51 of the magnifying lever 43 andtilts the latter until its shoulder 42 again underlies the lug 41. In this position the latching nose 45 passes the catch 46 at the free end of the thermostatic element 48, so that upon release of the lever 19 the magnifying lever 43 is held by the thermostatcatch 46 and-the rocking frame lug 41 is again supported in normal position on the shoulder 42. The mechanism is thus reset in open circuit position. Upon the retion and no visible indication of the overload condition is afforded. When a battery of Circuit breakers is used, the disadvantage of this lack of indication isapparent. Gur in vention is not restricted to the particular form of mechanism by which the indication is Y efiected, but is broadly directed to a mechanism of any character which afiords a telltale indication of the automatic opening of the circuit breaker on overload.

The circuit through the thermostatic element does not enter into our joint invention, and it sufiices to point out that the leg at of the thermostat is riveted to the bracket 52 (Fig. 4) which is engaged by the screw 53 taking into the base of the line terminal 24.

The other leg 6 of the thermostatic element is riveted to the bracket 54 which is connect; ed by screw 55 tothe shunt 56, and the latter in turn is connected by screw 27 to the base of the fixed contact 26.

We also wish to disclaim any joint invention broadly in the magnifying lever 43 and in the lost motion connection between the block'30 andthelever 31, by which a hammer blow is imparted to the block by the lever 31, on the opening of the circuit.

The thought which underlies the present joint invention is the provision of means for indicating the overload operation of the circuit breaker, and more particularly efiecting this indication by the position of the manually operated member. As above stated this automatically opened 2. A circuit breaker having a circuit breaker mechanism, a manually actuated member for operating said mechanism to make and break the circuit, and an overload responsive member controlling said mechanism to open the circuit on overload,

said manually actuated member assuming, on overload operation of the mechanism, an indicating position distinct from that assumed by it on manual operation thereof. 1

3. A circuit breaker having ,a circuit breaker mechanism, a rocking frame in which a certain portion of said mechanism is mounted, 'a manually operated member for actuating saidmechanism to open or close the circuit, and .overload responsive means ,normally maintaining said rocking frame in predetermined position but permitting the same to rock and 'o en the circuit under overload circuit conditions, and means governed by the overload position of said frame to indicate the overload opening of the circuit.

-4. A circuit. breaker having a circuit breaker mechanism, a rocking frame in wh1ch a certain portion of said mechanism is mounted, a manually operated member for.

its

neeaaei Q ually operated member to hold it in ositron to indicate the overload opening 0 the circuit.

In testimony whereof we have signed our names to this specification.

CARL ERIC ANDERSON. WILLIAM H. KEEFE, JR.

actuating said mechanism to open or close the circuit, and overload responsive means normally maintaining said rocking frame in predetermined position but permitting the 5 same to rock and open the circuit under overload circuit conditions, and means associated with said frame to engage said man DISOLMMER 1,656,851.Carl Eric Anderson, Stratford, and William H. Keefe, 3'12, Bridgeport, Conn. CIRCUIT BREAKER. Patent dated January 17, 1928. Disclaimer filed April 21, 1932, by assignee, The Bryant Electric Company.

Hereby enters this disclaimer to claims 1 and 2 in said-patent, which are in the following Words, to-wit:

1. A manually operable circuit breaker having associated means for automatically opening thecircuit on overload, a casing enclosing the circuit breaker mechanism an exteriorly visible indicator having normal on and off positions'on manual operation of the circuit breaker, and means locating said indicator in a different position when the circuit is automatically-opened on overload.

2. A circuit breaker having a circuit breaker mechanism, a manually actuated member for operating said mechanism to make and-break the circuit, and an overload responsive member controlling said mechanism to open the circuit on overload, said manually actuated member assuming, on overload operation of the mechanism, an indicating position distinct from that assumed by it on manual operation thereof.

[Oflicz'al Gazette May 10, 1982.] 

